Rotational Wireless Communication System

ABSTRACT

Disclosed by way of example embodiments is a wireless communication system transmitting or receiving a wireless signal according to an orientation of the wireless communication system. In one aspect, the wireless communication system includes an antenna operable in different configurations. In each configuration, the antenna has a corresponding antenna gain in a direction with respect to the antenna. The wireless communication system further includes a sensor for determining an orientation of the wireless communication system. According to the determined orientation, the antenna is configured to transmit or receive the wireless signal in a corresponding configuration. Hence, the wireless communication system disposed in different orientations can successfully communicate with another wireless communication system.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/381,951, filed Dec. 16, 2016, the contents of which is incorporatedby reference in its entirety.

TECHNICAL FIELD

This disclosure relates to a wireless communication system, and morespecifically, to the wireless communication system placed in differentorientations communicating with another wireless communication system.

BACKGROUND

Wireless communication systems communicate with each other bytransmitting and receiving wireless signals. A wireless communicationsystem includes an antenna that transmits or receives wireless signals.Generally, an antenna of a wireless communication system has a differentantenna gain depending on the orientation of the antenna with respect toan antenna of another wireless communication system. In particular, awireless signal directed in a particular direction associated with ahigh antenna gain may be transmitted or received without much loss,whereas another wireless signal directed in a different direction with alow antenna gain may be significantly suppressed. Likewise, an antennaof a wireless communication system has a different polarizationdepending on the orientation of the antenna with respect to an antennaof another wireless communication system. A wireless signal directed ina particular direction associated with a matched polarization may betransmitted or received without much loss, whereas another wirelesssignal with different polarization would be significantly suppressed.Thus, a wireless communication system oriented in a direction with ahigh antenna gain and matched polarization may establish a successfulwireless communication with another wireless communication system.However, a wireless communication system oriented in another directionwith a low antenna gain and mismatched polarization may fail toestablish a wireless communication with said another wirelesscommunication system.

BRIEF DESCRIPTIONS OF THE DRAWINGS

The disclosed embodiments have other advantages and features which willbe more readily apparent from the following detailed description of theinvention and the appended claims, when taken in conjunction with theaccompanying drawings, in which:

Figure (FIG.) 1 illustrates an example apparatus including a wirelesscommunication system, according to one embodiment.

FIG. 2 illustrates example components of the wireless communicationsystem, according to one embodiment.

FIG. 3 illustrates an example circuit diagram of the wirelesscommunication system, according to one embodiment.

FIG. 4A illustrates a plan view of an example antenna operable in atleast two configurations, according to one embodiment.

FIG. 4B illustrates a perspective view of the antenna in FIG. 4A,according to one embodiment.

FIG. 5 is a smith chart of an antenna operating in two differentconfigurations, according to one embodiment.

FIG. 6A illustrates a cross section of a radiation pattern of theantenna shown in FIGS. 4A and 4B operating in a first configuration,according to one embodiment.

FIG. 6B illustrates a cross section of a radiation pattern of theantenna shown in FIGS. 4A and 4B operating in a second configuration,according to one embodiment.

FIG. 6C illustrates a perspective view of a radiation pattern of theantenna operating in a first configuration, according to one embodiment.

FIG. 6D illustrates a perspective view of a radiation pattern of theantenna operating in a second configuration, according to oneembodiment.

FIG. 7 illustrates an example circuit diagram of the wirelesscommunication system, according to another embodiment.

FIG. 8A illustrates a plan view of an example antenna operable in atleast two configurations, according to another embodiment.

FIG. 8B illustrates a perspective view of the antenna in FIG. 8A,according to one embodiment.

FIG. 9 illustrates a circuit diagram of an example hybrid couplerincluded in the wireless communication system shown in FIG. 7, accordingto one embodiment.

FIG. 10 is a flow chart showing a process of detecting a position of acamera arranged in different orientations, according to the presentedembodiments.

DETAILED DESCRIPTION

The figures and the following description relate to preferredembodiments by way of illustration only. It should be noted that fromthe following discussion, alternative embodiments of the structures andmethods disclosed herein will be readily recognized as viablealternatives that may be employed without departing from the principlesof what is claimed.

Reference will now be made in detail to several embodiments, examples ofwhich are illustrated in the accompanying figures. It is noted thatwherever practicable similar or like reference numbers may be used inthe figures and may indicate similar or like functionality. The figuresdepict embodiments of the disclosed system (or method) for purposes ofillustration only. One skilled in the art will readily recognize fromthe following description that alternative embodiments of the structuresand methods illustrated herein may be employed without departing fromthe principles described herein.

Configuration Overview

Disclosed by way of example embodiments is a wireless communicationsystem that transmits or receives a wireless signal according to anorientation of the wireless communication system. In one aspect, thewireless communication system may include an antenna operable indifferent configurations. In each configuration, the antenna may have acorresponding antenna gain and polarization in a direction with respectto the antenna. The wireless communication system may further include asensor for determining an orientation of the wireless communicationsystem. According to the determined orientation, the antenna may beconfigured to transmit or receive the wireless signal in a correspondingconfiguration. Hence, the wireless communication system disposed indifferent orientations can successfully communicate with anotherwireless communication system.

Example Wireless Communication System

Figure (FIG.) 1 illustrates an example apparatus 100. By way of example,the apparatus 100 may include a camera. The apparatus 100 also mayinclude a wireless communication system 120, according to one exampleembodiment. The wireless communication system 120 may be integratedwithin or coupled to a body of the example apparatus 100 and/or camera.The wireless communication system 120 may wirelessly communicate withone or more external communication systems 110A, 110B, 110C, 110D. Theexternal communication systems 110A, 110B, 110C, 110D may be, forexample, satellite communication systems, broadcasting stations, mobilecommunication devices, etc.

The body of the example apparatus 100 may be a mechanical structure or aframe to which electronic devices (e.g., camera) can be coupled. In oneaspect, the wireless communication system 120 may communicate with theone or more of the external communication systems 110A, 110B, 110C, 110Daccording to an orientation of the example apparatus 100.

The example apparatus 100 in FIG. 1 includes a body that may partiallyor entirely enclose an electronic device (e.g., camera). The body of theexample apparatus 100 also may be coupled, through a mount 150, to anobject that is in motion or part of an object that is in motion (e.g.,helmet, hat, automobile, drone, snowboard, skateboard, extendable pole,etc.). As a result, an orientation of the wireless communication system120 varies according to a movement or an orientation of the movingobject. The wireless communication system 120 arranged in differentorientations can successfully communicate with the one or more of theexternal communication systems 110A, 110B, 110C, 110D (e.g.,satellites).

In one example, the electronic device enclosed by the apparatus 100operates together with the wireless communication system 120. Forexample, the electronic device is a camera that captures an image, andthe wireless communication system 120 is a global positioning system(GPS) receiver that determines a location of the image captured by thecamera. Despite the apparatus 100 may be subject to frequent movementsin various orientations, the wireless communication system 120 cansuccessfully determine the location of the apparatus 100.

FIG. 2 illustrates example components of the apparatus 100, according toone embodiment. A body of the apparatus 100 includes a surface to whicha lens 210 of a camera is coupled. In the example shown in FIG. 2, amarking 220 is provided on the surface to indicate an orientation of theapparatus 100. The body of the apparatus 100 further includes one ormore additional surfaces on which the wireless communication system 120is coupled. In some embodiments, a different electronic device otherthan the camera is coupled to the surface. In addition, the marking 220may be provided on a different portion of the body or may be omitted.

In one embodiment, the wireless communication system 120 includes anantenna 230, a wireless communication circuit 240, a switching unit 250,a sensor 260, and a controller 270. The antenna 230, the wirelesscommunication circuit 240, the switching unit 250, the sensor 260, andthe controller 270 are electrically coupled to each other. Together,these components operate together to detect an orientation of thewireless communication system 120, and configure the antenna 230 and/orthe switching unit 250 according to the detected orientation forestablishing a wireless communication. Some of these components may bedisposed on outer surface of the body of the apparatus 100 or disposedon an inner surface of the body. In some embodiments, the wirelesscommunication system 120 includes different, fewer or additionalcomponents than shown in FIG. 2.

The sensor 260 is a hardware component that detects an orientation ofthe apparatus 100. The sensor 260 may be an accelerometer or gyroscopesensor that detects the orientation of the apparatus 100, and generatesa detection signal according to the detected orientation. The detectionsignal is an electric signal indicating the detected orientation. Forexample, an accelerometer may be used to detect the orientation of theapparatus by determining the gravitational acceleration from measuringacceleration of the 3 principal axes (X, Y and Z). For another example,a gyroscope may be used to detect the orientation of the apparatus bytracking the rotation of the apparatus 100 around the 3 principal axes(X, Y and Z). Yet in another example, measurements from differentsensors can be combined to obtain more accurate orientation of theapparatus 100. The sensor 260 generates the detection signal accordingto the orientation of the apparatus 100 determined through the sensor260, and provides the detection signal to the controller 270.

The controller 270 is an electric component that receives the detectionsignal from the sensor 260, and configures the switching unit 250according to the detection signal. The controller 270 is electricallycoupled between the sensor 260 and the switching unit 250. According toan orientation of the apparatus 100 indicated by the detection signal,the controller 270 generates a control signal and provides the controlsignal to the switching unit 250. The control signal is an electricsignal that controls the switching unit 250 for changing a configurationof the antenna 230. The controller 270 may be embodied as amicroprocessor implemented on, for example, an application specificintegrated circuit (ASIC) or a field-programmable gate array (FPGA).

The switching unit 250 electrically connects the wireless communicationcircuit 240 to the antenna 230 in a certain configuration, according tothe control signal from the controller 270. The switching unit 250 maybe electrically coupled between the wireless communication circuit 240and the antenna 230. Additionally, the switching unit 250 iselectrically coupled between the controller 270 and the antenna 230.

The antenna 230 may be a component that allows a wireless signal to betransmitted or received through a wireless medium (e.g., air space). Theantenna 230 may include at least two feeds 232A, 232B, through whichelectric signals can be applied. Depending on the connections of thefeeds 232A, 232B, the antenna 230 operates in a certain configurationwith a corresponding antenna gain and polarization. In one example for acertain polarization, the antenna 230 operating in a first configurationhas a high antenna gain in a first direction with respect to the antenna230, but has a low antenna gain in a second direction with respect tothe antenna 230. In addition, the antenna 230 operating in a secondconfiguration has a low antenna gain in the first direction with respectto the antenna, but has a high antenna gain in the second direction withrespect to the antenna 230.

TABLE 1 Example of RHCP Gain at theta = 0 and 180 degree (phi = 0/180degree) in first configuration (ST1) and a second configuration (ST2).RHCP Gain Configuration ST1 ST2 Upwards (theta = 0 degree with 0 dBi−12.3 dBi respect to the antenna) Downwards (theta =180 degree with−17.4 dBi −3.1 dBi respect to the antenna)In one example, the antenna 230 is implemented as a patch antenna, andmay be right hand circular polarized. Alternatively, the antenna 230 maybe implemented as a different type of antenna (e.g., loop antenna,etc.), or polarized differently.

The wireless communication circuit 240 transmits or receives thewireless signal through the antenna 230. The wireless communicationcircuit 240 is electrically coupled to the antenna 230 through theswitching unit 250. The wireless communication circuit 240 includes atransmitting circuit, a receiving circuit, or both. In one example, thewireless communication circuit 240 may include a GPS receiving circuitthat receives a wireless signal from satellites through the antenna 230,downconverts the wireless signal, and determines a position of theapparatus 100 based on the downconverted wireless signal.

FIG. 3 illustrates a circuit diagram of the wireless communicationsystem 120, according to one embodiment. The wireless communicationsystem 120 includes the wireless communication circuit 240, theswitching unit 250A, and the antenna 230. The sensor 260 and thecontroller 270 are omitted for simplicity. The switching unit 250A iselectrically coupled between the wireless communication circuit 240 andthe antenna 230, and couples the wireless communication circuit 240 toeither a first feed 232A or a second feed 232B of the antenna 230according to a detection signal indicating an orientation of theapparatus 100.

In particular, the switching unit 250A includes a first port P1, asecond port P2, and a third port P3. The first port P1 is coupled to thewireless communication circuit 240 through a connection 310. The secondport P2 is coupled to the first feed 232A of the antenna 230 through aconnection 320A. The third port P3 is coupled to the second feed 232B ofthe antenna 230 through a connection 320B.

When a detection signal indicates that the apparatus 100 is oriented ina first orientation, the switching unit 250A electrically couples thefirst port P1 to the second port P2, such that the antenna 230 operatesin the first configuration. In the first configuration, the first feed232A of the antenna 230 is electrically coupled to the wirelesscommunication circuit 240, while the second feed 232B of the antenna 230is decoupled from the wireless communication circuit 240. When thedetection signal indicates that the apparatus 100 is oriented in asecond orientation, the switching unit 250A electrically couples thefirst port P1 to the third port P3, such that the antenna 230 operatesin the second configuration. In the second configuration, the secondfeed 232B of the antenna 230 is electrically coupled to the wirelesscommunication circuit 240, while the first feed 232A of the antenna 230is decoupled from the wireless communication circuit 240. Depending onthe connection through the switching unit 250A, the antenna 230 operatesin the first configuration or the second configuration.

FIG. 4A illustrates a plan view of an example antenna 230A operable inat least two configurations, according to one embodiment. FIG. 4Billustrates a perspective view of the antenna 230A shown in FIG. 4A,according to one embodiment. In one embodiment, the antenna 230Aincludes a ground plane 450, a substrate 460 on the ground plane 450, aradiator patch 400A within the substrate 460, and two feeds 232A, 232B.The substrate 460 may be a ceramic substrate and may have a generallyrectangular shape with side 480A, 480B, 480C, 480D. The feed 232A may bedisposed on the side 480A of the substrate 460, and the feed 232B may bedisposed on the side 480B of the substrate 460 adjoining the side 480A.The radiator patch 400A receives a wireless signal from a wirelessmedium (e.g., air space), and provides the received wireless signal tothe feed 232A, feed 232B or both through proximity coupling.Alternatively, the radiator patch 400A receives a wireless signal fromthe feed 232A, feed 232B or both through proximity coupling, andradiates the wireless signal to the wireless medium.

In one implementation, the radiator patch 400A comprises a conductivematerial and generally has a rectangular shape including sides 485A,485B, 485C, 485D each facing a respective one of the sides 480A, 480B,480C, 480D of the substrate 460. The radiator patch 400A additionallyincludes slits 410A, 410B and chamfers 420A, 420B.

Each chamfer 420 may be a cut out portion of a corresponding corner ofthe radiator patch 400A. In one example, the chamfer 420A is formed on acorner between the side 485C facing away from the feed 232A and the side485B facing the feed 232B. In addition, the chamfer 420B is formed on acorner between the side 485D facing away from the feed 232B and the side485A facing the feed 232A. Hence, chamfers 420A, 420B are formed ondiagonal corners of the radiator patch 400A. The chamfers 420A, 420Bgenerate two orthogonal modes with 90 degree phase difference betweenthem. The placement of each feed 232 relative to the corner chamfers 420determines the polarization as the phase difference between theorthogonal modes will either lag or lead. By switching a connection ofthe two feeds 232A, 232B, phase for the orthogonal modes and thepolarization of the antenna can be changed.

The slit 410A may be disposed on the side 485C of the radiator patch400A facing away from the first feed 232A, and the slit 410B may bedisposed on the side 485D of the radiator patch 400A facing away fromthe second feed 232B. In one example, the feed 232A is disposed near acenter of the side 480A and the feed 232B is disposed near a center ofthe side 480B, where the slit 410A is disposed near a center of the side485C and the slit 410B is disposed near a center of the side 485D. Theslits 410A, 410B are added to improve impedance matching and adjustresonance frequency, as shown in FIG. 5.

FIG. 5 illustrates a smith chart of the antenna 230A operating in twodifferent configurations, according to one embodiment. The smith chartshown in FIG. 5 shows S(1,1) plot 510 of the first feed 232A and S(1,1)plot 520 of the second feed 232B. As shown in FIG. 5, a point 515corresponding to a target frequency (e.g., 1.575420 GHz for GPS signal)of the S(1,1) plot 510 of the first feed 232A is close to a center ofthe smith chart. Similarly, a point 525 corresponding to the targetfrequency (e.g., 1.575420 GHz for GPS signal) of the S(1,1) plot 520 ofthe second feed 232B is close to the center of the smith chart. Hence,the impedance at the first feed 232A and the second feed 232B arematched at the target frequency. The slits 410A, 410B allow flexibilityof impedance matching or adjusting resonance frequency of the antenna230A.

FIG. 6A illustrates a cross section of the radiation pattern of theexample antenna 230A shown in FIGS. 4A, 4B operating in the firstconfiguration. FIG. 6B illustrates a cross section of the radiationpattern of the example antenna 230A shown in FIGS. 4A, 4B operating in asecond configuration. The orientation of the antenna 230A in FIG. 6B is‘180’ degree flipped with respect to the orientation of the antenna 230Ain FIG. 6A.

Referring to FIG. 6A, the wireless communication system 120 with theantenna 230A operating in the first configuration can communicate withanother wireless communication system 120 within a region 610 in a firstpolarization (e.g., right hand circular polarization). Thus, in thefirst polarization, the wireless communication system 120 cancommunicate with another wireless communication system 120 that isplaced further away from the wireless communication system 120 along a‘0’ degree direction with respect to the wireless communication system120 than another wireless communication system 120 placed along a ‘180’degree direction with respect to the wireless communication system 120.In addition, the wireless communication system 120 with the antenna 230Aoperating in the first configuration can communicate with anotherwireless communication system 120 within a region 620 in a secondpolarization (e.g., left hand circular polarization). Thus, in thesecond polarization, the wireless communication system 120 cancommunicate with another wireless communication system 120 that isplaced further away from the wireless communication system 120 along the‘180’ degree direction with respect to the wireless communication system120 than another wireless communication system 120 placed along the ‘0’degree direction with respect to the wireless communication system 120.

Referring to FIG. 6B, the wireless communication system 120 with theantenna 230A operating in the second configuration can communicate withanother wireless communication system 120 within a region 630 in a firstpolarization (e.g., right hand circular polarization). Thus, in thefirst polarization, the wireless communication system 120 cancommunicate with another wireless communication system 120 that isplaced further away from the wireless communication system 120 along a‘180’ degree direction with respect to the wireless communication system120 than another wireless communication system 120 placed along a ‘0’degree direction with respect to the wireless communication system 120.(Note the orientation of the wireless communication system 120 in FIG.6B is ‘180’ degree flipped compared to the one in FIG. 6A.) In addition,the wireless communication system 120 with the antenna 230A operating inthe second configuration can communicate with another wirelesscommunication system 120 within a region 640 in a second polarization(e.g., left hand circular polarization). Thus, in the secondpolarization, the wireless communication system 120 can communicate withanother wireless communication system 120 that is placed further awayfrom the wireless communication system 120 along the ‘0’ degreedirection with respect to the wireless communication system 120 thananother wireless communication system 120 placed along the ‘180’ degreedirection with respect to the wireless communication system 120.

FIG. 6C illustrates a perspective view of a radiation pattern of theantenna shown in FIGS. 4A and 4B operating in a first configuration,according to one embodiment. FIG. 6D illustrates a perspective view of aradiation pattern of the antenna shown in FIGS. 4A and 4B operating in asecond configuration, according to one embodiment.

Assuming that the wireless communication system 120 communicates withanother wireless communication system in the first polarization (e.g.,right hand circular polarization), the antenna 230A is configureddifferently according to an orientation of the wireless communicationsystem 120. For example, the antenna 230A operates in a firstconfiguration according to the switching unit 250A responsive to thewireless communication system 120 is placed in a first orientation asshown in FIG. 6C. Hence, the wireless communication system 120 cancommunicate with another wireless communication system within the region610 in the first polarization (e.g., right hand circular polarization).For another example, the antenna 230A operates in a second configurationaccording to the switching unit 250A responsive to the wirelesscommunication system 120 is placed in a second orientation as shown inFIG. 6D. Hence, the wireless communication system 120 can communicatewith another wireless communication system within the region 630 in thefirst polarization.

Alternatively, the wireless communication system 120 operates withopposite configurations than shown in FIGS. 6C and 6D to communicatewith another wireless communication system in the second polarization(e.g., left hand circular polarization). Specifically, the antenna 230Aoperates in the first configuration according to the switching unit 250Aresponsive to the wireless communication system 120 is placed in a firstorientation. Hence, the wireless communication system 120 cancommunicate with another wireless communication system within the region620 of FIG. 6A in the second polarization (e.g., left hand circularpolarization). For another example, the antenna 230A operates in thesecond configuration according to the switching unit 250A responsive tothe wireless communication system 120 is placed in a second orientationopposite to the first orientation. Hence, the wireless communicationsystem 120 can communicate with another wireless communication systemwithin the region 640 in the second polarization (e.g., left handcircular polarization).

FIG. 7 illustrates a circuit diagram of the wireless communicationsystem 120, according to another embodiment. The wireless communicationsystem 120 in this embodiment is similar to the one shown in FIG. 7,except the switching unit 250B is electrically coupled between thewireless communication circuit 240 and the antenna 230 instead of theswitching unit 250A. In this embodiment, the switching unit 250B issimultaneously coupled to the feeds 232A, 232B of the antenna 230,rather than being coupled to only one of the feeds at a time.

In particular, the switching unit 250B includes a hybrid coupler 710,and a switching circuit 750. The hybrid coupler 710 includes a singleended port S coupled to the wireless communication circuit 240 throughthe connection 310, and ports Da, Db coupled to the switching circuit750 through connections 715A, 715B, respectively. The switching circuit750 includes ports 1A, 1B coupled to the ports Da, Db throughconnections 715A, 715B, respectively, and ports 2A, 2B coupled to thefeeds 232A, 232B through the connections 320A, 320B, respectively. Inone aspect, the hybrid coupler 710 converts a single ended signal of theconnection 310 into two signals of the connections 715A, 715B with aphase difference (e.g., 90 degree). The switching circuit 750 providesthe signals to the antenna 230, according to the detection signalindicating the orientation of the apparatus 100. In another exampleaspect, the switching circuit 750 receives the signal from the antenna230, according to the detection signal indicating the orientation of theapparatus 100. Subsequently, the hybrid coupler 710 may combine thesignals of the connections 715A, 715B into the single ended signal ofthe connection 310.

When the detection signal indicates that the apparatus 100 is orientedin a first orientation, the switching unit 250B electrically couples theport 1A to the port 2A, and electrically couples the port 1B to the port2B, such that the antenna 230 operates in the first configuration. Whenthe detection signal indicates that the apparatus 100 is oriented in asecond orientation, the switching unit 250B electrically couples theport 1A to the port 2B, and electrically couples the port 1B to the port2A, such that the antenna 230 operates in the second configuration.Depending on the connections through the switching circuit 750, theantenna 230 may operate in the first configuration or the secondconfiguration.

FIG. 8A illustrates a plan view of an example antenna 230B operable inat least two configurations, according to another embodiment. FIG. 8Billustrates a perspective view of the antenna 230B in FIG. 8A, accordingto one embodiment. The antenna 230B shown in FIGS. 8A and 8B can beimplemented in the wireless communication system 120 shown in FIG. 7.The configuration of the antenna 230B is similar to the antenna 230Ashown in FIGS. 4A and 4B except the slits 410A, 410B and the chamfers420A, 420B are omitted. Therefore, the detailed descriptions of theconfiguration and the operation of the antenna 230B are omitted for thesake of brevity.

In the wireless communication system 120 shown in FIG. 7, a phasedifference is achieved through the hybrid coupler 710, whereas in thewireless communication system 120 shown in FIG. 3, a phase difference isachieved through the chamfers 420A, 420B of the antenna 230A.Accordingly, the wireless communication system 120 in FIG. 7 canimplement a simpler antenna 230B as shown in FIGS. 8A and 8B than theantenna 230A as shown in FIGS. 4A and 4B.

FIG. 9 illustrates a circuit diagram of an example hybrid coupler 710,according to one embodiment. In one embodiment, the hybrid coupler 710includes capacitors C1, C2, C3, inductive elements L1, L2, L3, L4, and atermination circuit Z5. Each of the inductive elements L1, L2, L3, L4may include an inductor, and the termination circuit Z5 may include aresistor (e.g., 50 ohms) for providing a proper termination. In otherembodiments, the hybrid coupler 710 may include different, fewer, oradditional components than shown in FIG. 9.

In one implementation, the capacitor C1 is coupled between the singleended port S and the port Da. The capacitor C2 is coupled between afirst node n1 and a second node n2. The capacitor C3 is coupled betweena third node n3 and the port Db. In addition, the inductive element L1is coupled between the single ended port S and the first node n1. Theinductive element L2 is coupled between the port Da and the second noden2. The inductive element L3 is coupled between the first node n1 andthe third node n3. The inductive element L4 is coupled between thesecond node n2 and the port Db. Moreover, the termination circuit Z5 iscoupled between the third node n3 and a reference voltage (e.g.,ground). In this arrangement, the single ended signal of the singleended port S is converted into two signals with a phase difference(e.g., 90 degree). Additionally or alternatively, the signals of theports A and B are converted into the single ended signal of the singleended port S.

FIG. 10 is a flow chart showing a process of detecting a position of acamera arranged in different orientations, according to one exampleembodiment. The steps in FIG. 10 may be performed by the wirelesscommunication system 120 of the apparatus 100 partially or entirelyenclosing the camera. In some embodiments, the wireless communicationsystem 120 may perform different, fewer, or additional steps than shownin FIG. 10.

The wireless communication system 120 determines 1010 an orientation ofthe camera. For example, a gyroscope or accelerometer determines anorientation of the camera, and generates a detection signal indicatingthe orientation of the camera.

The wireless communication system 120 controls 1020 a switching unit 250coupled to the antenna 230 according the detection signal. The switchingunit 250 couples a GPS receiver (e.g., wireless communication circuit240) to the antenna in a configuration according to the orientation ofthe camera indicated by the detection signal.

The wireless communication system 120 receives 1030 a wireless signalfrom GPS satellites through the antenna 230. Moreover, the GPS receiverdownconverts the wireless signal, and determines 1040 a position of thecamera based on the downconverted signal. The GPS receiver mayautomatically determine a position of the camera, when the cameracaptures an image.

Additional Configuration Considerations

Advantageously, the wireless communication system disposed in differentorientations can successfully communicate with another wirelesscommunication system by configuring an antenna according to differentorientations of the wireless communication. In particular, a singleantenna may be electrically connected in different arrangementsaccording to the orientation of the wireless communication system, wherethe antenna operating in each configuration has different antennapolarization gain for a given direction. Hence, the wirelesscommunication system can transmit or receive a wireless signal indifferent orientations using a single antenna without employing multipleantennas.

Throughout this specification, some embodiments have used the expression“coupled” along with its derivatives. The term “coupled” as used hereinis not necessarily limited to two or more elements being in directphysical or electrical contact. Rather, the term “coupled” may alsoencompass two or more elements that are not in direct contact with eachother, but yet still co-operate or interact with each other, or arestructured to provide a thermal conduction path between the elements.The term “electrically coupled” may encompass two or more electricalcomponents electrically connected to each other through conductivematerials. The term “electrically decoupled” may encompass two or moreelectrical components not electrically connected to each other throughconductive materials.

Likewise, as used herein, the terms “comprises,” “comprising,”“includes,” “including,” “has,” “having” or any other variation thereof,are intended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus.

In addition, use of the “a” or “an” are employed to describe elementsand components of the embodiments herein. This is done merely forconvenience and to give a general sense of the invention. Thisdescription should be read to include one or at least one and thesingular also includes the plural unless it is obvious that it is meantotherwise.

Finally, as used herein any reference to “one embodiment” or “anembodiment” means that a particular element, feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. The appearances of the phrase “in oneembodiment” in various places in the specification are not necessarilyall referring to the same embodiment.

Upon reading this disclosure, those of skilled in the art willappreciate still additional alternative structural and functionaldesigns as disclosed from the principles herein. Thus, while particularembodiments and applications have been illustrated and described, it isto be understood that the disclosed embodiments are not limited to theprecise construction and components disclosed herein. Variousmodifications, changes and variations, which will be apparent to thoseskilled in the art, may be made in the arrangement, operation anddetails of the method and apparatus disclosed herein without departingfrom the spirit and scope defined in the appended claims.

What is claimed is:
 1. An apparatus comprising: a body partially enclosing a camera; a sensor coupled to the body, the sensor configured to generate a detection signal indicating an orientation of the body; an antenna coupled to the body, the antenna comprising a first feed and a second feed; a receiver circuit coupled to the body; and a switch electrically coupled between the receiver circuit and the antenna, the switch configured to electrically configure a connection between the receiver circuit and the first feed and the second feed of the antenna, responsive to the detection signal indicating the body being oriented in a first orientation.
 2. The apparatus of claim 1, wherein the antenna is configured to receive a wireless signal.
 3. The apparatus of claim 2, wherein the receiver circuit is configured to receive the wireless signal and downconvert the wireless signal.
 4. The apparatus of claim 3, wherein the receiver circuit is a global positioning system receiver configured to determine a position of the body according to the downconverted wireless signal.
 5. The apparatus of claim 1, wherein the switch is configured to: electrically decouple the receiver circuit from the second feed of the antenna and electrically couple the receiver circuit to the first feed of the antenna, responsive to the detection signal indicating the body being oriented in the first orientation.
 6. The apparatus of claim 1, wherein the switch is configured to: electrically decouple the receiver circuit from the first feed of the antenna and electrically couple the receiver circuit to the second feed of the antenna, responsive to the detection signal indicating the body being oriented in a second orientation.
 7. The apparatus of claim 1, comprising: a hybrid coupler electrically coupled between the receiver circuit and the switch, the hybrid coupler comprising a single ended port, and two additional ports with a phase difference, the single ended port coupled to the receiver circuit, the two additional ports comprising a first port and a second port.
 8. The apparatus of claim 7, wherein the switch is configured to: electrically couple the first port to the first feed of the antenna and electrically couple the second port to the second feed of the antenna, responsive to the detection signal indicating the body being oriented in the first orientation.
 9. The apparatus of claim 7, wherein the switch is configured to: electrically couple the second port to the first feed of the antenna and electrically couple the first port to the second feed of the antenna, responsive to the detection signal indicating the body being oriented in a second orientation.
 10. The apparatus of claim 7, wherein the phase difference is 90 degree.
 11. The apparatus of claim 1, wherein the antenna is right hand circular polarized in a first direction, when the first feed is electrically coupled to the receiver circuit responsive to the detection signal indicating the body being oriented in the first orientation.
 12. The apparatus of claim 11, wherein the antenna is right hand circular polarized in a second direction, when the second feed is electrically coupled to the receive circuit, responsive to the detection signal indicating the body being oriented in a second orientation.
 13. The apparatus of claim 12, wherein the first direction is opposite to the second direction.
 14. The apparatus of claim 1, wherein the first feed is disposed on a first side of the antenna and the second feed is disposed on a second side of the antenna, the first side and the second side adjoining each other at a first corner of the antenna.
 15. The apparatus of claim 14, wherein the antenna comprises a first chamfer and a second chamfer, the first chamfer formed on a second corner of the antenna at an end of the second side from the first corner, the second chamfer formed on a third corner of the antenna at an end of the first side away from the first corner.
 16. The apparatus of claim 1, wherein the sensor is a gyroscope or accelerometer configured to determine the orientation of the body.
 17. An apparatus comprising: a body partially enclosing a camera; a sensor coupled to the body, the sensor configured to generate a detection signal indicating an orientation of the body; an antenna coupled to the body, the antenna comprising a first feed and a second feed; a receiver circuit coupled to the body; and a switch electrically coupled between the receiver circuit and the antenna, the switch configured to electrically configure a connection between the receiver circuit and the first feed and the second feed of the antenna, responsive to the detection signal indicating the body being oriented in a first orientation or in a second orientation.
 18. The apparatus of claim 17, wherein the switch is configured to: electrically decouple the receiver circuit from the second feed of the antenna and electrically couple the receiver circuit to the first feed of the antenna, responsive to the detection signal indicating the body being oriented in the first orientation.
 19. The apparatus of claim 17, wherein the switch is configured to: electrically decouple the receiver circuit from the first feed of the antenna and electrically couple the receiver circuit to the second feed of the antenna, responsive to the detection signal indicating the body being oriented in the second orientation.
 20. A camera comprising: a body; a sensor, the sensor configured to detect an orientation of the body; an antenna, the antenna comprising a first feed and a second feed; a receiver circuit; and a switch configured to electrically configure a connection between the receiver circuit and the first feed and the second feed of the antenna, responsive to the orientation of the body indicating the body being oriented in a first orientation or in a second orientation. 